The video, taken from store cameras, captured U.S. Immigration and Customs Enforcement agents rounding up 24 men suspected of being illegal immigrants. Most have since been deported or left the country voluntarily.

In the video, agents can be seen ignoring black store patrons while focusing on Latino men. Advocates say a white man who had hired three Latinos for day labor was allowed to drive his pickup truck away from the 7-Eleven, while the three workers were taken into custody.

In addition, the advocates say, the video shows agents detaining a number of Latinos who had been waiting at a bus stop across the street from the 7-Eleven, a common hiring spot for day laborers.

"Today, with this video, we're fighting back," said Jessica Alvarez, chairwoman of the National Capital Immigration Coalition. "Today, we are showing everyone exactly what our community has been telling us about the abuses, about the racial profiling."

Alvarez spoke at a late-morning news conference at a Fells Point church a few blocks from the 7-Eleven on South Broadway.

Richard Rocha, a spokesman for Immigration and Customs Enforcement, said he had not seen the footage. But he denied that agents engaged in racial profiling. "These allegations were thoroughly investigated in 2007 and were deemed to be unsubstantiated," he said.

CASA de Maryland, a Silver Spring-based immigrant advocacy group with a Baltimore office, released the footage. The group announced that it had filed a federal lawsuit last month against the Department of Homeland Security seeking internal documents on the roundup.

The group has received a partially blacked-out report by Homeland Security's Office of Professional Responsibility. The report is redacted after a statement noting that "some of the circumstances surrounding the presence of the officers at the 7-Eleven have come into question."

CASA also said it had filed wrongful-arrest claims for three of the detained men. One has since voluntarily returned to El Salvador. The two others are free on bond in Baltimore while fighting government attempts to deport them. The men are seeking $500,000 apiece.

CASA obtained the footage in 2007 but did not release it earlier because of pending immigration cases, said staff attorney Justin Cox. It also wanted to give the government a "fair shot" to investigate, but an independent accounting has not occurred, Cox said.

Rocha, of ICE, called the roundup proper. "In this case, our officers used their training and experience to respond to a developing situation as it unfolded. They were approached by individuals asking if they needed workers. Those workers were questioned, and ultimately it was determined they were in the country illegally."

The footage shows several Latinos approaching a car as it pulls into the 7-Eleven parking lot. But Cox said agents in that vehicle did not identify themselves and instead posed as contractors. The roundup began moments later as additional ICE agents arrived.